|Year : 2021 | Volume
| Issue : 2 | Page : 214-220
Complexity of root canal treatment: Evaluation of cases using the restorative index of treatment need system: A descriptive cross sectional study
Joan Emien Enabulele, Louis O Ibhawoh
Department of Restorative Dentistry, School of Dentistry, University of Benin, Benin City, Edo State, Nigeria
|Date of Submission||06-Jun-2020|
|Date of Decision||14-Jul-2020|
|Date of Acceptance||30-Jul-2020|
|Date of Web Publication||8-May-2021|
Dr. Joan Emien Enabulele
Department of Restorative Dentistry, School of Dentistry, University of Benin, P. O. Box: 10427, Benin City, Edo State
Source of Support: None, Conflict of Interest: None
Introduction: The complex anatomy of the root canal system, the challenging oral environment as well as some patient factors tend to pose challenges to realizing endodontic treatment goals. The aim of this study was to evaluate the complexity of root canal treatment using the Restorative Index of Treatment Need (RIOTN) system.
Materials and Methods: This was a descriptive cross-sectional study of patients who received endodontic treatment between May 2018 and July 2019. The data obtained were medical history, tooth for endodontic treatment, and clinical and radiographic findings. The RIOTN system was applied to grade the complexity of root canal treatment. All data garnered were statistically analyzed using IBM SPSS software.
Results: The sample population consisted of 114 patients with 124 root-treated teeth. In all, 12.9% of the teeth were graded as complexity Grade 3, 14.5% as Grade 2, and 72.6% as Grade 1. Modifying factors were present in 13.7% of the teeth, with the most prevalent modifying factor being endodontic re-treatment. There was no statistically significant association between number of roots of the teeth and complexity grade (P = 0.57).
Conclusion: It is important to grade the complexity of teeth in order to predict the prognosis of treatment and decide whether it is within one's proficiency.
Keywords: Assessment, complexity, endodontics, Restorative Index of Treatment Need, root canal treatment
|How to cite this article:|
Enabulele JE, Ibhawoh LO. Complexity of root canal treatment: Evaluation of cases using the restorative index of treatment need system: A descriptive cross sectional study. Saudi Endod J 2021;11:214-20
|How to cite this URL:|
Enabulele JE, Ibhawoh LO. Complexity of root canal treatment: Evaluation of cases using the restorative index of treatment need system: A descriptive cross sectional study. Saudi Endod J [serial online] 2021 [cited 2021 Jun 17];11:214-20. Available from: https://www.saudiendodj.com/text.asp?2021/11/2/214/315637
| Introduction|| |
Root canal treatment is primarily concerned with the control of infection within the root canal system through the eradication of microorganisms and the prevention of re-infection. The complex anatomy of the root canal system, the challenging oral environment as well as some patient factors tend to pose challenges to realizing these endodontic treatment goals. Knowledge of pulpal anatomy, its usual and possible variations as well as unusual configurations is critical for success in endodontics, and lack of such knowledge may lead to treatment failure. There are many reasons why root canal treatment may fail. One of the main reasons for the failure of root canal treatment has been reported to be the inadequate removal of pulp tissue and microorganisms from the root canal system.
Research has focused on the effect of the quality of root canal filling on the outcome of treatment. A review reported that a number of Swedish studies detected that inadequate root-filling quality was associated with periapical inflammation. Another study reported that only 10% of root fillings performed in England and Wales were of a satisfactory technical quality. A review of cases in Scotland showed that 54% of root fillings were not satisfactory.
It has been suggested that, as the complexity of root canal treatment increases, the more difficult it may become to achieve high technical standards. A high level of competence in undertaking root canal treatment procedures is required in general dental practice as general dental practitioners regard root canal treatment as a complex, mysterious procedure enveloped in uncertainty. Furthermore, dental students tend to report difficulty with endodontic treatment, with the students referring difficult cases and re-treatment cases to postgraduate students.
There is growing evidence that certain factors may enable a clinician to envisage the expected outcome of root canal therapy and thus better inform the patient of the likely success rates accordingly. The capability to forecast treatment outcome is critical to making a choice whether to treat or not to treat with dental students preferring to perform endodontic treatment that is within their expertise limit. All clinicians must be able to predict the prognosis of endodontic treatment, make an informed decision about its complexity, and agree whether it is within their proficiencies before they obtain informed consent from patients.
Endodontic failures have been shown to be more related to the lack of knowledge, lack of continuing education courses on the part of the general dental practitioners as well as the lack of proper specialized instruments, proper training on the use of these instruments when they are used, the complex anatomy of the teeth, and the lack of referral of such patients to the specialists. A favorable prognosis in root canal treatment relies on the clinician's experience, skills, and expertise on addressing the challenge to overcome the complex canal morphology, neutralize the microbial pathogenicity regardless of the type and duration of infection, and disrupt the bacterial biofilm.,
Various indices have been used to assess the complexity of root canal treatment.,,,,,,, However, the Restorative Index of Treatment Need (RIOTN) system has been reported not to be field tested. The complexity assessment is an important component of RIOTN that can be used following clinical examination in order to assess the complexity of the treatment problem identified. Each complexity component has a series of three core codes (low – 1, moderate – 2, and high – 3) to which a modifying factor may apply. A modifying factor can only increase a complexity score by one code increment, they are not cumulative.
Assessing the complexity of root canal treatment predictably and reliably could help to identify the most appropriate setting in which a patient should receive treatment,,, allow correlation with treatment outcomes as well as a valuable tool in risk management, or to select suitable cases of root canal treatment for undergraduates. Furthermore, the RIOTN system is one of such index, though rapid and easy to use, it has been reported not to be field tested.
Hence, this study was designed to evaluate the complexity of root canal treatment in a tertiary hospital in Nigeria using RIOTN system index in order to identify a valuable tool to select suitable cases for root canal treatment for the various levels of practitioners.
| Materials and Methods|| |
This was a descriptive cross-sectional study of patients who received endodontic treatment between May 2018 and July 2019. The endodontic treatment was carried out by resident doctors in the Department of Restorative Dentistry and consisted of conventional root canal treatment and surgical endodontic treatment where indicated. The filling technique employed was lateral condensation. The procedures for this study were in accordance with the ethical standards of the responsible committee on human experimentation (institutional or regional) and with the Helsinki Declaration of 1975, as revised in 2000. Ethical approval was sought and obtained from the Research and Ethics Committee of the University of Benin Teaching Hospital (ADM/E22/A/Vol. VII/1405), and written informed consent was obtained from all participants.
The criteria for selection of participants for this study were patients with at least one tooth indicated for endodontic treatment and who gave informed consent to participate in the study. The data collection instrument obtained information regarding medical history, the tooth indicated for endodontic treatment, clinical findings, and radiographic findings. The radiographic findings were obtained by taking intraoral digital periapical radiographic images using direct digital radiographs (RVG 5100, Carestream, Germany) of each tooth in question using the long-cone paralleling technique, and when additional information was required, an additional parallax view was obtained. The images were evaluated using the RVG 5100 software and reviewed by 2 senior residents with intra-examiner variability of k = 0.82 and 0.83, and in case of difference in opinion, the radiographic image in contention was shown to a more senior dentist for his opinion. The curvature radius of the curved root canals was determined using a method described in previous studies.,
The RIOTN system was applied to grade the complexity of root canal treatment using the three scoring codes (low – 1, moderate –2, and high –3) to which a modifying factor may apply. Teeth with either single or multiple root canals with root curvature(s) <15° to root axis which are considered negotiable from radiographic or clinical evidence through their entire length, without root canal obstruction or damaged access, and do not require incision and drainage are graded as complexity 1.
Teeth with single/multiple root canals with curvature >15° but <40° to root axis that are considered negotiable from radiographic or clinical evidence through their entire length or have incomplete root development are graded as complexity 2.
Teeth with single/multiple root canals with curvature >40° single/multiple root canals that are not considered negotiable from radiographic or clinical evidence through their entire length, requiring periradicular surgery, have iatrogenic damage or pathological resorption, or have difficult root morphology are graded as complexity 3.
A modifying factor can only increase a complexity score by one code increment, they are not cumulative. After application of the modifying factor, the final complexity grade is obtained. The modifying factors that are relevant to root canal treatment as stated in RIOTN system are:
Co-ordinated medical (e.g., renal: cardiac) and/or dental (e.g., oral surgery: orthodontic) multidisciplinary care; medical history that significantly affects clinical management; special needs for the acceptance or provision of dental treatment; presence of a retching tendency; mandibular dysfunction; atypical facial pain; undiagnosed facial pain; endodontic re-treatment; limited conventional or surgical operating access; surgery in the proximity of important anatomical structures, for example, mental foramen; surgery where there is periodontal pocketing >3.5 mm; patient requires intramuscular or intravenous medication as a component of clinical management; patient has a history of head/neck radiotherapy; patient is significantly immunocompromised or immunosuppressed; patient has a significant bleeding dyscrasia/disorder; and patient has a potential drug interaction.
All data garnered were analyzed using This should read IBM SPSS statistics for windows version 21.0 (IBM Corp. Armonk, N.Y., USA). The statistical tools employed were descriptive statistics in the form of frequency counts, percentage, and cross tabulations. Associations between variables were tested using Chi square test and Fischer's exact test where applicable with P set at 0.05.
| Results|| |
The sample population consisted of 114 patients who had nonsurgical endodontic treatment performed on 124 teeth. Multirooted teeth accounted for 54.0%, single-rooted teeth accounted for 46.0% of the teeth evaluated, and re-treatment was encountered in 6.45% of the cases.
Majority (81.5%) of the teeth evaluated had single/multiple root canals with curvature <15° to root axis that are considered negotiable from radiographic or clinical evidence through their entire length and no root canal obstruction or damaged access. Incision and drainage were carried out in 6.5% of the teeth. Single/multiple root canals with curvature >15° but <40° to root axis that were considered negotiable from radiographic or clinical evidence through their entire length were observed in 10.5% of the teeth evaluated. Difficult root morphology was encountered in 5.6% of the cases, whereas 3.2% had iatrogenic damage or pathological resorption, and 6.5% of the cases were re-treatment cases [Table 1].
Modifying factors were present in 13.7% of the teeth evaluated. The most prevalent modifying factor was endodontic re-treatment accounting for 47.1% of the teeth that had associated modifying factor, whereas the least modifying factor was the presence of a retching tendency seen in 5.9% of those that had modifying factor [Table 2]. In all, 12.9% of the teeth were graded as complexity Grade 3, 14.5% as Grade 2, and 72.6% as Grade 1.
|Table 2: Distribution of modifying factors among cases with modifying factors|
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[Table 3] shows the distribution of codes by complexity grade. Among the teeth awarded complexity Grade 1, 97.7% had single/multiple root canals with curvature <15° to root axis that were considered negotiable from radiographic or clinical evidence through their entire length and had no root canal obstruction or damaged access, whereas 7.8% required incision and drainage. Of the teeth graded as complexity 2, 38.9% had single/multiple root canals with curvature >15° but <40° to root axis that were considered negotiable from radiographic or clinical evidence through their entire length, whereas the remaining teeth were graded as complexity 2 due to the presence of modifying factors. Among teeth awarded complexity 3, 43.7% were teeth with difficult root morphology, 25.0% were teeth with iatrogenic damage or pathological resorption, whereas teeth with single/multiple root canals with curvature >40° or single/multiple root canals that were not considered negotiable from radiographic or clinical evidence through their entire length accounted for 6.3% each. The remaining were due to the presence of modifying factors.
The modifying factors associated with teeth graded as complexity 2 and 3 are depicted in [Table 4]. The most prevalent modifying factor associated with complexity Grade 2 was endodontic re-treatment (60.0%) and with complexity Grade 3 was surgery in the proximity of important anatomical structures, for example, mental foramen (42.9%). There was no statistically significant association between number of roots of the teeth and complexity grade [Table 5].
|Table 4: Distribution of modifying factors associated with complexity Grades 2 and 3|
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|Table 5: Association between number of roots of the teeth and complexity grade|
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| Discussion|| |
A successful index should be capable of converting a clinical finding into a numerical index which can be used to compare one patient with another or to group patients into common categories. A look at the most frequently used indices showed that the successful ones have been very specific in the stage of care they measure. This is important in order to achieve an index in which the value ascribed by the index can be relied on to record a valid clinical situation.
Root canal treatment is one of the most technically challenging procedures and a very specialized part in restorative dentistry, demanding high levels of technical skills. Therefore, if the choice of root canal treatment is made, the clinician must be able to predict the probable difficulties that may be met and subsequently determine whether they are within their capability. The root canal complexity assessment is an important component of the ROITN, following a clinical examination it can be used to assess the complexity of the treatment problem identified.
The pattern of provision of endodontic treatment in this study showed that multirooted teeth accounted for a greater proportion corroborating the alteration in pattern of root canal-treated teeth with a greater involvement of multirooted posterior teeth.,,,,,
Endodontic treatments can differ significantly in their complexity, with some cases being straightforward with negligible risks of complications, whereas others may require advanced technical skills and expertise. Therefore, it was not surprising to note that all the teeth evaluated had varying grades of complexity. In all, 12.9% of the teeth evaluated in this study were graded as complexity Grade 3, 14.5% as Grade 2, and 72.6% as Grade 1. This is contrary to reports of a previous study which had 5% of the root-treated teeth graded as complexity 1, 48% of teeth graded as complexity 2, and 47% of teeth were graded as complexity 3 and another study in which treatment complexity was most often code 2 or code 3. This may be because the center where this study was carried out is not strictly a specialist endodontic clinic but a restorative clinic which has endodontics as a subspecialty compared to the previous study which was strictly an endodontic clinic. Such specialized endodontic clinics tend to receive high and moderate complexity root canal treatments. However, the findings of this study may be comparable to a previous Nigerian study which reported minimal difficulty among 70% of cases using the American Association of Endodontists difficulty assessment.
The prevalence of teeth with single/multiple root canals with curvature <15° to root axis (81.5%) was higher than that reported (64.4%) in a previous study. The proportion of single/multiple root canals with curvature >15° but <40° to root axis (10.5%) seen in this study was less than that reported (30.6%) in a previous study among general dental practitioners. Atypical pulp and root canal morphology have been associated with increased complexity of nonsurgical root canal treatments, with curved canals being one of the most encountered factors affecting complexity.
It is believed that numerous factors may affect the complexity of root canal treatment. This is seen in this study as modifying factors increased the complexity grade of case with modifying factors present in 13.7% of the teeth evaluated, with the most prevalent modifying factor being endodontic re-treatment. However, the prevalence of re-treatment cases seen in this study (6.5%) is lower than the 7.5% reported in a previous Nigerian study and far lower (15.6%) than that observed in general dental practice. Re-treatment cases have been reported to be second to caries as indication for endodontic treatment, this may be the reason why it was the most prevalent modifying factor observed in this study.
Among teeth awarded complexity 3 in this study, teeth with difficult root morphology made up the highest proportion of teeth in this grade, followed by teeth with iatrogenic damage or pathological resorption. This pattern is different from that reported in a previous study where teeth awarded complexity Grade 3 had a higher proportion having iatrogenic damage or pathological resorption, followed by nonnegotiable canal. Successful root canal treatment averts pain, apical periodontitis, and tooth loss, but it is a real challenge when clinical conditions such as iatrogenic damage or pathological resorption exist, indication for a poor prognosis. It has been recommended that most iatrogenic damages be managed by more experienced clinicians under high magnification surgical microscope or at least optical loupes.
Teeth with single/multiple root canals with curvature >40° accounted for 6.3% of the cases. The prevalence was higher than 4.1% reported in a previous study. The most prevalent modifying factor associated with complexity Grade 2 in this study was endodontic re-treatment, a finding similar to a previous report.
Limitation of this study
The endodontic treatment was performed by resident doctors no matter the complexity grade. Further research is needed to assess the complexity of endodontic treatment with different cadre of dentists and dental students performing the different grades and outcomes assessed to identify the competency levels of the dental students and cadre of dentists.
| Conclusion|| |
It is important to grade the complexity of teeth in order to predict the prognosis of treatment and decide whether it is within one's proficiency. The authors found the RIOTN system a practical index for use in predicting and assessing the complexity of root canal treatment. Once embraced by undergraduate dental students and general dental practitioners, the RIOTN system properly classifies treatment complexities, which can then be matched with proficiency and capability through timely and appropriate referrals to specialist endodontists, leading to the likelihood of better treatment outcomes.
The authors acknowledge the residents and house officers who were on rotation in the department during the period of this study for their support.
Financial support and sponsorship
The authors solely sponsored the research.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]